Wireless charging is to realize the energy transmission between the power supply and the electric equipment in a non-contact wireless way. Currently available wireless charging technologies include electromagnetic induction, magnetic resonance, radio wave, ultrasonic, infrared laser and electric field coupling. The most widely used wireless charging technology is electromagnetic induction, which has the advantages of high conversion efficiency and short-distance charging. The principle of electromagnetic induction technology is that a changing current flows through a coil to generate a changing magnetic field, and the paired coils are coupled to generate a corresponding voltage for charging.
Among them, electromagnetic induction is the most used technology in the current mobile phone market, and magnetic resonance technology has huge future potential and is expected to become the mainstream technology. The principle of electromagnetic induction is that the power transmitting coil and the power receiving coil are built in the charging base and the mobile phone terminal respectively. When the two are close, the transmitting coil (transmitting coil) is based on the alternating current of a certain frequency in the mobile phone receiving coil (receiving coil) ) Generates a certain current, thereby transferring electric energy from the transmitting end to the receiving end, and supplying power from the charging dock to the mobile phone. The electromagnetic induction method is relatively simple to implement and is currently the most mainstream solution in mobile phones. The main problem is that the transmission distance is severely limited. Magnetic induction wireless charging can only support one-to-one wireless charging, and it has defects such as low charging power and short charging distance. In order to achieve one-to-many wireless charging, improve power and have more flexible and free charging distances, magnetic resonance wireless Charging has begun to receive industry attention.
